Motor-controller.



H- G. R BENNETT.

MOTOR CONTROLLER.

APPLICATTON HLED MAR. 12. 1915.

1,233,959. Patented July 17, 12117.

INVENTOP.

T T l T l HERBERT G. R. BENNETT, OF YOUNGSTOWN, OHIO.

MOTOR-CONTROLLER.

Specification of Letters Patent.

Patented July 17,1917.

Application filed March 12, 1915. Serial 1%. 13 ,921.

To all whomit may concern Be it known that I, HERBERT G. R. BEN- nn'r'r, a citizen of the United States, residing in Youngstown,- Ohio, have invented certain' new and useful Improvements in Motor- Gontrollers', of which the following is a specification.-

This invention aims to provide a motor controller which is especially, though not exclusively, designed for variable speed,wound rotor, induction motors, by means of which the varying of the speed can be effected very imply and quickly.

The accompanying drawings illustrate an embodiment of the invention.

Figure 1 is a longitudinal vertical section;

Fig. 2 a transverse vertical section;

Fig. 3 a diagrammatic view of the motor and the controlling circuits.-

Referring now to the" embodiment of the invention illustrated, a three-phase line A is connected bymeans of a suitable switch B to the three terminals C of the motor controller whence the current is carried to the three separate spring contacts D. Below the latter are three separate spring contacts E connected with. the terminal wires F of the primary windings of the motor G. The

secondary windings of the motor connect with wires H, the ends of which are con nected with vessels J containing bodies of liquid K, which are to be connected with each other with a varying degree of resistance in order to vary the speed of the motor.

The spring contacts of each pair D and E are adapted to be connected to and disconnected from each other by means of rods or tubes L, one for each pair of contacts so arranged that after making contact the rods can be moved through a considerable range and still maintain the circuits unchanged.

Means are provided for short circuiting the wires H of the secondary windings, such means comprising a bar M of conductive material electrically connected to and actually carrying three plates N of similar material adapted to enter the liquid in the re spective vessels to a variable extent and thus to vary the resistance in the secondary windings.

The contact device comprising the sprin contacts D and E and the rods L, all 0 which are designated as a whole by the letter O, Fig. 3, and the variable resistance device which is similarly designated by the letter P are arranged to be operated by a coinmon means and to move simultaneously. The rods L move vertically so that their connection with the vertically movingplates N is of the simplest. After the rods L have moved down sufficiently to make contact at E they can be moved farther while maintaining the contact unchan'ged, while the same movement varies the extent of contact of the plates N with the liquid K and thus varies the resistance in this device.

Figs. 1 and 2 show the mechanical arrangement devised for this purpose. A sheet metal casing Q open at front and back carries a cross-bar R from which are suspended the several vessels J, each of which is provided near the bottomwith a brass contact spring S' an'd' each of which is electrically connected with one of the wires H. When the plates N advance so far as to come into contact with the spring S the'rcsistance is reduced to a minimum. Above-the'several vessels are the tapered contact plates N carried on-a cross-bar M which is'connected at its ends to upwardly extending rods T connected attheir upper ends to a crossbar U. Extending between the sides of the casing Q is a cross-bar or floor V upon which is supported a casing W closed on the ends, sides and bottom. Over the top of this casing extends a second cross-bar resting on the top of the casing Q. From the cross-bar X end brackets Y extend upwardand are provided with vertical guideways Z in which the ends of the cross-head U are engaged and guided. In the end brackets Y there are provided also bearings for a laterally extending shaft a which carries a weighted handle I) and which has near its ends inwardly extending arms 0, the ends of which are connected by means of links (l to the cross-head U; so that the raising and lowering of the lever b raises and lowers the cross-head.

The contacting rods or tubes L are guided by non-conducting bushings through the cross-bar X, and the rods T are similarly guided. The rods L are connected by insulating joints at their upper ends to extensions which are bolted to the cross-head U. The contacts D and E are separately mounted upon plates 7 and g of nonconducting material by means of bolts 7:. passing through said plates and through the crossbar X and by means of spacers j surrounding said bolts.

In operating the apparatus the operator will raise the lever 72 and this movement will simultaneously cause the contact rods L to make contact with the springs E, and no matter to what height the lever 72 is lifted 5 the rods L passing through the holes provided for the purpose in the supporting plates f and 9 will continue to make the same degree of contact with the springs D and E. The same upward movement of the lever 7) brings the plates N into contact with the bodies of liquid K, but as the lever is lifted higher the extent of contact is increasedand the resistance decreased gradually-until at the limit of the stroke the plates N come into contact with the springs S in the bottom of the vessels, which establishes the minimum resistance.

Though I have described with reat particularity of detail a certain speci c embodiment of my invention yet it is not to be understood therefrom that the invention is restricted to the particular embodiment illustrated and described. Various modifications thereof in detail and in the arrangement of the parts may be made by those skilled in the art without departure from the invention.

What I claim is 1. A motor controller comprising in com bination contacts in vertical line with each other, a rod adapted to be moved vertically over said contacts so as to maintain the circuit between them unchanged in various po sitions of vertical adjustment, and a variable resistance device comprising a solid member connected to said rod so as to move vertically therewith and a vessel for holding a body of liquid into which said solid member is brought to a variable extent by such vertical motion.

2. A motor controller comprising in combination a plurality of pairs of contacts, a

- plurality of rods, one for each pair of contacts and movable over its contacts so as to maintain the circuits between them unchanged in various positions of adjustment, a cross-head carrying said rods, and a va riable resistance device comprising a plurality of solid members connected to said crosshead so as to move therewith and vessels for holding bodies of liquid into which the respective solid members are brought to a variable extent by such motion.

3. In a motor controller, the combination with a contact device having members arranged for relative vertical reciprocatory movement while in contact, and a variable resistanc device having a reciprocatory plate member adapted to move into a body of liquid to a variable extent, of means connecting the plate member of said resistance device to the movable members of said contact device, to thereby cause said members to reciprocate in unison, and means connected to said contact device for actuating the reciprocating members of said devices.

et. In a motor controller, the combination with a contact device having stationary members and a reciprocatory member adapted to move vertically over said stationary members while in contact therewith and a variable resistance device including a vessel adapted to contain a body of liquid and having a contact member at the bottom thereof, of a reciprocating plate member adapted to move into said body of liquid to a variable extent and to engage with the contact member at the bottom of said vessel, means connecting said reciprocatory member and said plate member and adapted to move said members in unison and means for operating said reciprocatory members, said operating means moving through a distance proportional to that of the plate lmember of said variable resistance device.

5. In a motor controller, the combination with a contact device having relatively re-t ciprocable members adapted to be moved over each other while in contact, and a variable resistance device including a vessel adapted to contain a body of liquid and hav ing a reciprocable plate member arranged to move into said body of liquid to a variable-extent, of means connecting the movable members of said contact device with the reciprocable plate -member of said resist-. ance device and adapted to cause simultaneous movement of said members to the same distances and to maintain said contact while varying said resistance and means for actuating the movable members of said devices.

In witness whereof, I have hereunto signed my name in the presence of two subscribing witnesses.

HERBERT G. R. BENNETT. Witnesses:

FLOYD C. LEYSHON, ALBERT MARKUS.

Copies of this patent may be obtained for five cents each, by addressing the Commissioner of Patents,

Washington, D. C. 

